224 / 2024-07-26 17:23:23

Deep red light driven hydrogen evolution by heterojunction polymer dots for diabetic wound healing

photocatalysis,hydrogen evolution,heterojunction polymer dots,diabetic wound healing

Hydrogen as a therapeutic agent has attracted a great deal of attention because of its superior therapeutic outcome on many diseases, including inflammatory injury, tumors, metabolic disorders, and neurological diseases. Photocatalytic hydrogen evolution has emerged as a promising strategy for hydrogen production and delivery. We developed small heterojunction polymer dots (Pdots) with deep-red light catalyzed H₂ generation for diabetic skin wound healing. The Pdots with donor/acceptor (D/A) heterojunctions showed remarkably enhanced photocatalytic activity as compared to the donor (PTB7-Th) or acceptor (EH-IDTBR) nanoparticles alone. We encapsulate the Pdots and ascorbic acid (AA) into liposomes to form Lipo-Pdots nanoreactors, which selectively scavenge •OH radicals in live cells and tissues under 650 nm light illumination. According to the experiment results, the antioxidant capacity of the heterojunction Pdots was determined to be ~10 times higher than that of the single-component Pdots. Cellular assays and mouse paw studies indicated that the Lipo-Pdots nanoreactors under the deep-red 650 nm light irradiation apparently eliminated LPS-induced ROS in macrophages and mitigate subcutaneous inflammation. Under a light dose of 360 J/cm², which is comparable to those in photodynamic therapy, the Lipo-Pdots effectively scavenged •OH radicals and suppressed the expression of pro-inflammatory cytokines in skin tissues, thereby accelerating the healing of skin wounds in diabetic mice. This work provides a useful strategy for safe and effective treatment of diabetic foot ulcers.